For the purpose of exploring uranium deposits in Pingxiashui area of Nanxiong City, Guangdong Province，the authors applied the fractal data-processing method to determining the anomaly lower limit of the radioactive exploration data. Then the results obtained by this method were compared with those obtained by the conventional data processing method of "average value plus three times of variance". The results show that the fractal method can be applied to the processing and interpretation of radioactive exploration data, with its effect better than that of the conventional method. The metallogenic prognosis based on data-processing of fractal theory would provide the basis for further prospecting.